I wasn't sure if my first post when through, so I created a second one.

Form 1: tasty and quick, these little critters are the lowest on the food-chain. They eat decaying
materials; letting their roots sink in to pull the nutrition out of them. When they detect a threat,
they quickly retract their roots and run away. For the most part, these creatures are very shy, however they can get aggressive if you approach their nest or if they feel confident enough in their numbers to swarm the intruder. The swarms can be very vicious, especially if they manage to get you to the ground. Light them on fire or get out!

Form 2: at this point, the creature has learned where to gather its resources and what areas to avoid. The tentacles on some of its roots start to develop new growths that require a ton of energy from the creature which causes it to actively seek food. It becomes a bit of a pest during this stage in its life, as it will get into your garbage or dig up dead and decaying materials to feast on. Instead of running from predators, this creature tends to dig in its roots and attempts to blend
in with the environment. If worse comes to worse, the creature will club and strike at the hostile.

Form 3: no longer able to carry its massive body the creature settles down into an area it will
consider home for the rest of its life, digging in its roots. With its new arms and ripe mushrooms, the monster now waits for prey to come to it. This creature is VERY territorial, as it plans to
grow babies. So once it is confident it has secured its position, it begins to grow Eyes. Once
these babies mature, they break off from the main body and start their own life, sometimes sticking around the parent until their hunger drives them out to find more food...or until 'mama' eats them when resources become scarce (driving the babies away).